1. Field of the Invention
The invention relates to the field of ethanol production from plant-based fluids, and more particularly to application of radiation to such fluid.
2. Discussion of the State of the Art
Ethanol is an organic substance obtained from the fermentation of sugars, hydration of ethylene, or acetaldehyde reduction widely used as a process for production of fuel for engine combustion.
The “wort” is the juice of any fruit or vegetable that contains sugar, upon fermentation, and before completely purified by it. It is an intermediate product common to several processes, such as in the production of ethanol from sugar cane, sugar beets, and other vegetables. The result of fermentation of the wort is called wine. The wort is an organic fluid naturally contaminated by a range of microorganisms that will compete with the yeast incorporated into the mixture (for fermentation) in the production of ethanol. This problem is common to these techniques, and the existence of a wide range of bacteria in these plants that contaminate the wort is well known in the art. This combination is responsible for reducing bacterial productivity of these processes.
Microorganisms contaminate the process of production of alcohol, represented by bacteria and yeast that settle in the process. These contaminants are causing problems such as the consumption of sugar that would otherwise be converted into ethanol, decreased viability of yeast cells because of toxins excreted in the fluid by the microorganisms, flocculation of yeast that causes loss of yeast cells by the fund in the dressage or spin, and consequent fall in the industrial output. Furthermore, the formation of gum increases viscosity of the broth, causing operational problems in the production facility.
The juice of sugar cane contains varying amounts of organic and inorganic nutrients, high water activity, favorable pH and temperature conditions, and therefore provides for great growth of microbial flora. The very conditions of each stage of the production of alcohol select for microorganisms and the whole process is subject to contamination from the sugar cane field until the fermentation of its broth.
Yeasts and bacteria contaminants can produce lactic acid and other organic acids that, in quantities exceeding the normal, may be responsible for a decrease in the yield of fermentation. When this bacterial contamination reaches levels above 107 cells/ml, a significant drop in the yield of the alcohol may occur, and out-of-control bacterial contamination may indirectly cause a reduction in yield of fermentation because of the increased viscosity of the broth causing a greater loss of yeast broth centrifuged and higher consumption of sugar, diverting this from the production of sugar and alcohol.
The form currently used to overcome this problem in the art is the addition to the wort of various antibiotics, thereby reducing bacterial contamination. However, this process entails some new drawbacks among which are:                High cost of antibiotics        Need for periodic study of the range of bacterial contamination        Effects of bacterial action on yeast reduce productivity        Continued use of antibiotics can lead to biological and environmental problems by being re-released into the environment such as with, for example, the creation of resistant bacterial species        
What is needed is a sterilization procedure that avoids the use of antibiotics.